Firefox is a privacy respecting browser, available for major operating systems. Privacy Focused Website Blocker (by Avrodh.com) can be used to block websites on this browser.
Once you have installed the browser extension, you can find it in the "Extensions" menu of your browser.
Open the settings page
Once you have installed our browser extension, open the settings page. You can access it by clicking the extension icon in your browser's extensions menu.
Creating a block list on Firefox
Make a new list if one hasn't already been created. Otherwise, you can edit any existing list.
Enter the website you want to block in the edit interface, for example, example.com or https://example.com.
Save the list by clicking the save button.
Website is blocked on Firefox
Open a new tab in Mozilla Firefox and visit the blocked site. You’ll see it won’t load, and Firefox will display a blocked page instead.